Canberra, Australia - Climate change has reared up again as a major factor in the Australian political landscape, even as the issue has dropped substantially down the list of important issues for the electorate.

For most commentators: "It's the economy, stupid." But, over the past seven years, government and opposition positions on what should be done about climate change have had a greater impact on personal and party political fortunes than has the economy.

The solid advice and action from the Treasury and the Reserve Bank did more to keep Australia in good economic shape in the face of the global financial crisis than the actions of any politician.

The polls are suggesting that a great majority of Australians think Labor will lose the election on Saturday, and that the country will again be in the hands of a conservative Liberal-National Party coalition. The polls suggest that enough Australians will vote for the Coalition to give it a comfortable majority.

Australia's opposition buoyed by polls

But in the last week of the campaign, the opposition leader and head of the Liberal Party, Tony Abbott, asserted that the election was a referendum on the carbon tax - the Labor government's response to climate change.

Even if he wins the election with a majority in the House of Representatives, it is extremely unlikely that he will win a majority in the Senate, and the Senate must approve any legislation to repeal the tax.

Labor and Greens together have a majority in the Senate. Only half the Senate is elected on Saturday and the new senators do not take their seats until July 1, 2014.

So if Abbott becomes Prime Minister there is no guarantee he can repeal the tax. The Greens - with nine senators - have said they would definitely vote against repeal and the Labor leader, Prime Minister Kevin Rudd, has strongly hinted his party would join them.

If the Senate rejects the repeal legislation twice, the Prime Minister is entitled to call a double dissolution election for both the House and the Senate. It would mean Australians returning to the polls within a year.

Rudd was in precisely that position in 2008 when the Senate knocked back his initial carbon-pricing legislation because the coalition thought it too costly and the Greens thought it too weak. Some commentators hypothesise that if he had called a double dissolution election in 2008, Labor would be in much better shape right now.

Climate change had been a central issue in the 2007 election. Rudd called it "the greatest moral, economic and social challenge of our time", but after the Senate rejected his legislation he abandoned pricing carbon.

It made him look as though he lacked conviction.

In November 2009, Tony Abbott toppled Malcolm Turnbull as leader of the Liberal Party after differences over pricing carbon. Turnbull wanted to price carbon; Abbott would have none of it.

After Julia Gillard toppled Rudd as Labor leader and called an election in 2010, she said: "There will be no carbon tax under the government I lead, but I am determined to price carbon."

Proposed legislation

After the election, her minority government did introduce a carbon tax - of $26 a tonne. It gave Abbott the golden opportunity to denounce her as a liar and to campaign against the tax with a huge scare campaign, at one stage saying that the mining town of Whyalla would be "wiped off the map" by the carbon tax.

The tax came and Whyalla still stands. Nonetheless, the carbon tax shaped Abbott's electoral strategy for the better part of the past three years. And it looks like shaping his strategy well into the next term - and maybe beyond.

Instead of a carbon tax or a price on carbon, Abbott has proposed a "Direct Action" plan to reduce carbon emissions by five percent by 2020. The plan which subsidises energy efficiency and investment in renewables has been met with a high-degree of scepticism. The Australia Institute suggested it would yield about 18 percent of the needed abatement, based on Australian National Audit Office figures - meaning Australia's emissions would likely rise under Direct Action, rather than fall.

Moreover, Abbott has capped spending on the plan at $A3.2bn (3bn USD), even if the targets are not met.

However, Labor has not made much headway fighting this argument, or indeed with other policy weaknesses of the coalition. One reason is that it is not only fighting Abbott, but also against a full-blown anti-Labor pro-coalition campaign by Rupert Murdoch's News Ltd newspapers - which dominate the Australian newspaper market with 70 percent of the metropolitan circulation and about the same in internet penetration.

On August 6, the day after the election was announced - the Daily Telegraph's front page splashed a huge headline over a picture of Rudd making the announcement saying: "Kick this mob out".

Murdoch's aggressiveness

All the Murdoch papers have had similar anti-Labor banner headlines on Page One, urging voters not to vote Labor.

The journalist-mocking adage "never let the facts get in the way of a good story" has been remastered by the Murdoch press as: "Never let the facts get in the way of a bad story about the Labor government." Rudd has shrugged it off as the price of free speech in a democracy, but one does not know whether he does so from magnanimity - or fear of unleashing a worse onslaught if he were to fight back.

He says voters will make up their own minds, but in such a dominated media it can hardly be upon the basis of information fairly presented. Also, barely a week into the campaign, it appeared people had made up their minds and turned off. Polls are showing that young people in particular are not interested.

So the initial boost Labor got from Rudd's return to the leadership has long since gone. It has the boost it got from Rudd's promises to move to a market price on carbon, which would cut the levy from $26 a tonne to about $6 - and to curb people smuggling of refugees by promising to send all refugees arriving by boat to Papua New Guinea, denying them any chance of ever permanently settling in Australia.

Labor's disability support scheme and extra education spending have been matched by the coalition and are no longer selling points.

Labor's attack on Abbott's stature in foreign affairs has come to nothing. Australia takes on the presidency of the US Security Council this month, at a critical time in negotiations over military intervention in Syria. The fact that Australia is on the Security Council is largely due to Rudd's former work as foreign minister.

When Abbott heard Australia was seeking the role in 2011, his response was: "I don't think we should be spending money we don't have to promote a cause which is unlikely to come to anything."

Polls had previously revealed disquiet about Abbott's fitness and stature to be Australia's leader, particularly in world forums. That disquiet, too, has faded. Instead, concerns are rising about Rudd's reputation for policy-on-the-run; his failure to finish or deliver his programs; and his reputation for petulance in private.

Polls now have Abbott ahead of Rudd as preferred prime minister, and he will almost certainly assume the office after the vote comes in on Saturday night.

Crispin Hull was Editor of The Canberra Times for seven years and has taught journalism at the University of Canberra for ten years. He now teaches at the Australian National University.